Definition
An ablation is an experiment that removes, disables, or changes one component while holding the rest of the system as constant as practical. The difference in measured behavior estimates what that component contributes under the tested conditions.
Agent ablations might remove memory, retrieval, a planning step, a tool, or a verifier. Report the exact replacement condition. Removing a verifier and also reducing the token budget does not isolate the verifier's effect.
Components can interact. A tool may add little on its own but become valuable when paired with retrieval, or a planning step may help only on long tasks. One-at-a-time ablations should therefore be read as conditional evidence, not a complete causal map of the system.
Distinguish it from nearby terms
An ablation estimates component contribution. A benchmark compares systems under a common protocol. A sensitivity analysis varies a parameter across values rather than simply removing a component.
Check your understanding
Removing long-term memory does not change average accuracy, but it doubles repeated tool calls. An ablation that records only final accuracy misses a real contribution.